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Examining a biological flapping-flight mechanism as a mechanical system provides valuable insight related to the development and construction of Flapping-Wing Micro Air Vehicles (FWMAVs). Insects provide excellent candidates for this reverse-engineering, and one species in particular, the hawkmoth Manduca sexta, stands out as an exceptional model. Engineers with FWMAV aspirations can benefit greatly from knowledge of M.sexta's advanced yet deceptively simple flight mechanism. Avenues for investigating this mechanism include finite element modeling, nanoindentation for material properties, and mechanical power output calculations or measurement. This paper presents these concepts and reviews existing literature to provide a platform for ongoing FWMAV research and design. INTRODUCTIONVery small, autonomous, and agile MAVs with hovering capability are desirable for military and civilian applications. These flying robots, which will almost certainly require flapping wings to meet the hovering requirement, will be useful for gathering information in nearly any dangerous scenario which precludes direct human participation. For example, a FWMAV equipped with air-quality sensors could enter a contaminated building or area, enabling rescuers to determine the nature of the contaminant and whether it is or when it will be safe to enter. [3,4,6].M.sexta's thorax/wing structure can be modeled as a mechanical spring system (Fig. 1). Loads applied to the thorax by the flight muscles cause compression which in turn moves the wings through hinges on either side of the thorax. Relating force and compression yields energy, or work done. Data of this type furthers the understanding of this biological organism from a mechanical standpoint, and provides a basis to which current and future FWMAVs can be compared.The mechanical power output of this system can be found if the time during which this force and compression take place is known. It is well-known that flapping flight, especially in the low Reynolds conditions that M.sexta and FWMAVs experience [1], is "energetically demanding" and requires a very high power density [2]. This constitutes a challenge to engineers searching for micro power sources and delivery mechanisms for FWMAVs. Understanding the power density of the flight muscles of insects like M.sexta provides a much-needed benchmark which engineers can aspire to meet or surpass with their own power sources.Cuticle, the material which comprises the plates of the insect exoskeleton, plays a significant role in the performance of this flapping mechanism. Examining the material properties of these flexible, possibly energy-storing components will be key for future FWMAV technological advances. The elastic modulus of the thoracic cuticle of M.sexta will serve as a benchmark to which synthetic materials, potential FWMAV components, might be compared. Tensile tests can divulge the elastic modulus of the cuticle, but nanoindentation is a simpler and non-destructive approach which yields the same results. The latter is a...

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Manduca Sexta present excellent flight performances which make this insect an ideal candidate for bio-inspired engineered micro air vehicles. The actual insect presents an energetically very efficient thorax-wing flight system which needs to be fully understood for an effective design of artificial flying machines. This work discusses a preliminary finite element model which simulates the thorax-wing system and the muscles involved in the flapping motion. Both upstroke and downstroke conditions are statically analyzed with the application of load sets that simulate the contractions of the dorso-ventral and dorso-longitudinal muscles (indirect flight). Comparison with commercial software and experimental results is also presented and discussed.